docs(readme): fix broken examples, correct counts, surface missing features (#209)

* docs(readme): correct widget-type count from 21 to 19

The DashboardWidgetRegistry seeds exactly 19 built-in widget types
(verified via DashboardWidgetRegistry.types() in a live session and by
counting concrete *Widget.m classes in libs/Dashboard/). The README
claimed 21 in three places (badges line, dashboard feature list, and
What's in the box). Corrected all three to match the code.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): replace wrong '6 themes' with accurate themes + palettes

FastSenseTheme has only 2 distinct presets (light, dark) — the four
legacy names (default/industrial/scientific/ocean) all alias to light,
and the engine's own error says 'Use light or dark'. The '6' conflated
the 2 themes with the 4 separate line-color palettes (vibrant, muted,
colorblind, ocean). Replaced '6 themes' with 'light & dark themes,
4 color palettes', verified against a live FastSenseTheme() session.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): fix broken TagRegistry.register calls in Tags example

The Tags quickstart called TagRegistry.register(press) with a single
argument, which errors at runtime (MATLAB:minrhs — register's signature
is register(key, tag)). Verified the original snippet throws and the
two-arg form renders cleanly end-to-end in a live MATLAB session.
Corrected both calls to pass the tag key:
  TagRegistry.register('press_a', press)
  TagRegistry.register('press_high', alarm)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): fix broken dashboard example (Label->Title, MonitorTag->Threshold)

The 'Build a dashboard' quickstart errored at runtime in two ways,
both verified in a live MATLAB session:

1. 'Label' is not a valid widget option (DashboardWidget:unknownOption).
   number/gauge/status widgets all document 'Title'. Changed Label->Title.
2. A MonitorTag bound via 'Tag' routes to the Sensor slot (Sensor is a
   backward-compat alias for Tag), and StatusWidget then reads .Y, which
   MonitorTag lacks (MATLAB:noSuchMethodOrField 'Y'). StatusWidget's
   documented contract wires a MonitorTag-backed indicator via
   'Threshold'. Changed the status widget to 'Threshold', alarm.

Corrected snippet now renders all 4 widgets and round-trips through
save/load cleanly (ok=1, 4 widgets reloaded).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): correct examples count (40+ -> 70+) and run_all_examples claim

Two inaccuracies in the examples line, both verified against examples/:
- '40+ runnable scripts' undercounts — there are 72 example_*.m scripts
  in the topic dirs (01-basics .. 07-advanced), 82 .m files total.
- 'Run them all with run_all_examples' is misleading: run_all_examples
  executes a hardcoded curated list of 23 examples (prints
  'FastSense Examples (23 total)'), not all 72. All 23 curated files
  exist on disk.
Rewrote to '70+ runnable scripts ... run_all_examples plays a guided
tour of the highlights.'

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): add missing DerivedTag (5th Tag flavour)

The Tags section said 'four flavours' and listed only 4, but there are
5 concrete Tag subclasses (SensorTag, StateTag, MonitorTag, CompositeTag,
DerivedTag) — verified via superclasses() in a live session. DerivedTag
is the continuous-output counterpart to the 0/1 Monitor/Composite tags;
the README's own prose already promised 'derived signals' with no
matching table row.

- four -> five flavours; added a DerivedTag row (continuous signal from
  other tags). Verified DerivedTag computes power=V.*I correctly over
  1000 pts (matches expected to 1e-9).
- tightened CompositeTag's description to '0/1 aggregated from monitors'
  to distinguish it from the continuous DerivedTag (per CompositeTag's
  own header).
- added DerivedTag to the 'What's in the box' Tag list.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): surface per-widget info popups (flagship dashboard feature)

The README listed the dashboard's nested-layout and detach features but
omitted per-widget info popups — one of the three flagship features of
the Advanced Dashboard work. Every DashboardWidget has a Description
('Doc text shown in a popup when the widget's info (i) button is
clicked'); a non-empty Description renders an InfoIconButton that opens
a doc popup.

Verified in a live render: a widget WITH a Description shows exactly 1
InfoIconButton; a sibling without one shows none.

Added 'per-widget info popups' to the dashboard feature line and
'info popups' to the What's-in-the-box Dashboards recap.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(readme): rename example variable fp -> fs (FastPlot relic)

The quickstart code blocks named the FastSense handle 'fp' — an
abbreviation of the project's old name (FastPlot). Renamed both blocks'
variable to 'fs' so the front-door examples match the current product
name. Verified the renamed '30 seconds in' snippet still renders
cleanly (ok=1).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Author: HanSur94

README.md

@@ -8,7 +8,7 @@
 
 [![Tests](https://github.com/HanSur94/FastSense/actions/workflows/tests.yml/badge.svg)](https://github.com/HanSur94/FastSense/actions/workflows/tests.yml) [![Benchmark](https://github.com/HanSur94/FastSense/actions/workflows/benchmark.yml/badge.svg)](https://hansur94.github.io/FastSense/dev/bench/) [![codecov](https://codecov.io/gh/HanSur94/FastSense/graph/badge.svg)](https://codecov.io/gh/HanSur94/FastSense) [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE) [![MATLAB](https://img.shields.io/badge/MATLAB-R2020b%2B-orange.svg)](https://www.mathworks.com/products/matlab.html) [![Octave](https://img.shields.io/badge/GNU%20Octave-7%2B-blue.svg)](https://octave.org) [![Platform](https://img.shields.io/badge/Platform-Linux%20%7C%20macOS%20%7C%20Windows-lightgrey.svg)](#install)
 
-`100M+ points` · `Tags` · `live event detection` · `21 dashboard widgets` · `no toolboxes`
+`100M+ points` · `Tags` · `live event detection` · `19 dashboard widgets` · `no toolboxes`
 
 </div>
 
@@ -38,10 +38,10 @@ install;   % run once: adds paths + builds MEX accelerators
 x = linspace(0, 100, 1e7);              % 10 million points
 y = sin(x) + 0.1 * randn(size(x));
 
-fp = FastSense('Theme', 'dark');
-fp.addLine(x, y, 'DisplayName', 'Sensor');
-fp.addThreshold(0.8, 'Direction', 'upper', 'ShowViolations', true);
-fp.render();
+fs = FastSense('Theme', 'dark');
+fs.addLine(x, y, 'DisplayName', 'Sensor');
+fs.addThreshold(0.8, 'Direction', 'upper', 'ShowViolations', true);
+fs.render();
 ```
 
 That renders in **a few milliseconds and stays at 200+ FPS while you zoom and pan**. MATLAB's built-in `plot()` takes ~3 seconds on the same data and crawls at ~2 FPS. ([benchmarks ↓](#performance))
@@ -50,14 +50,15 @@ That renders in **a few milliseconds and stays at 200+ FPS while you zoom and pa
 
 ## The core idea: Tags
 
-Everything in FastSense — sensors, machine states, alarms, derived signals — is a **Tag**. One unified type, four flavours:
+Everything in FastSense — sensors, machine states, alarms, derived signals — is a **Tag**. One unified type, five flavours:
 
-| Tag            | What it is                                                  |
-|----------------|-------------------------------------------------------------|
-| `SensorTag`    | A measured time-series (pressure, temperature, …)           |
-| `StateTag`     | A discrete system state (idle / running / fault, recipe)    |
-| `MonitorTag`   | A derived 0/1 alarm signal — "is this sensor out of spec?"  |
-| `CompositeTag` | An aggregation of other tags                                |
+| Tag            | What it is                                                   |
+|----------------|--------------------------------------------------------------|
+| `SensorTag`    | A measured time-series (pressure, temperature, …)            |
+| `StateTag`     | A discrete system state (idle / running / fault, recipe)     |
+| `MonitorTag`   | A derived 0/1 alarm signal — "is this sensor out of spec?"   |
+| `CompositeTag` | A 0/1 signal aggregated from multiple monitors               |
+| `DerivedTag`   | A continuous signal computed from other tags (power = V × I) |
 
 Tags carry their own metadata (units, criticality, labels) and live in a shared **`TagRegistry`** so every part of the system — plots, dashboards, event detection, the web bridge — speaks the same language.
 
@@ -68,13 +69,13 @@ press.updateData(t, pressure_data);
 % Alarm whenever pressure > 55 bar
 alarm = MonitorTag('press_high', press, @(x, y) y > 55);
 
-TagRegistry.register(press);
-TagRegistry.register(alarm);
+TagRegistry.register('press_a', press);
+TagRegistry.register('press_high', alarm);
 
-fp = FastSense();
-fp.addTag(press);
-fp.addTag(alarm);     % overlaid as a 0/1 step trace
-fp.render();
+fs = FastSense();
+fs.addTag(press);
+fs.addTag(alarm);     % overlaid as a 0/1 step trace
+fs.render();
 ```
 
 The same `alarm` tag drives event detection, lights up status widgets in the dashboard, fires notifications, and shows up in the browser bridge — without you re-declaring the rule four times. For monitors that depend on multiple parents (e.g., a state-conditional alarm), compose them via `CompositeTag`.
@@ -89,17 +90,17 @@ Compose monitoring dashboards from widgets on a 24-column grid. The same Tags dr
 d = DashboardEngine('Process Monitor');
 d.Theme = 'dark';
 d.addWidget('fastsense', 'Position', [1 1 16 8],  'Tag', press);
-d.addWidget('number',    'Position', [17 1 8 4],  'Tag', press, 'Label', 'Pressure');
-d.addWidget('gauge',     'Position', [17 5 8 4],  'Tag', press, 'Label', 'Live');
-d.addWidget('status',    'Position', [1 9 24 2],  'Tag', alarm, 'Label', 'Alarm');
+d.addWidget('number',    'Position', [17 1 8 4],  'Tag', press, 'Title', 'Pressure');
+d.addWidget('gauge',     'Position', [17 5 8 4],  'Tag', press, 'Title', 'Live');
+d.addWidget('status',    'Position', [1 9 24 2],  'Threshold', alarm, 'Title', 'Alarm');
 d.render();
 
 d.save('process.json');           % JSON-persist
 % later:  d = DashboardEngine.load('process.json');
 ```
 
-- **21 widget types** — plots, numbers, gauges, status lights, gantt timelines, heatmaps, tables, markdown, …
-- **Multi-page tabs · collapsible groups · pop-out detached widgets**
+- **19 widget types** — plots, numbers, gauges, status lights, gantt timelines, heatmaps, tables, markdown, …
+- **Multi-page tabs · collapsible groups · per-widget info popups · pop-out detached widgets**
 - **Live mode** — synchronised refresh on a configurable timer
 - **Browser bridge** — `WebBridge(d).serve()` exposes the dashboard over TCP to a FastAPI + uPlot frontend
 
@@ -124,10 +125,10 @@ The trick: per-pixel **MinMax** and **LTTB** downsampling (SIMD C kernels with p
 
 ## What's in the box
 
-- **Plotting engine** — 100M+ point time-series, 6 themes, linked axes, datetime support, optional MEX SIMD kernels
-- **Tag domain model** — `SensorTag`, `StateTag`, `MonitorTag`, `CompositeTag`, shared `TagRegistry`
+- **Plotting engine** — 100M+ point time-series, light & dark themes, 4 color palettes, linked axes, datetime support, optional MEX SIMD kernels
+- **Tag domain model** — `SensorTag`, `StateTag`, `MonitorTag`, `CompositeTag`, `DerivedTag`, shared `TagRegistry`
 - **Event detection** — group violations into events, statistics, live pipeline, interactive Gantt viewer, notifications
-- **Dashboards** — 21 widget types, JSON persistence, multi-page, collapsible, detachable, live refresh
+- **Dashboards** — 19 widget types, JSON persistence, multi-page, collapsible, info popups, detachable, live refresh
 - **Browser bridge** — TCP → FastAPI → uPlot, bidirectional callbacks
 - **Disk-backed storage** — SQLite chunks with WAL for live reads, pyramid-cached downsamples
 - **Pure MATLAB / Octave** — no toolboxes, no internet, no licenses
@@ -153,7 +154,7 @@ MEX is optional — pure-MATLAB fallbacks kick in if no C compiler is available.
 
 ## Examples & docs
 
-40+ runnable scripts in [`examples/`](examples/), grouped by topic (`01-basics` … `07-advanced`). Run them all with `run_all_examples`.
+70+ runnable scripts in [`examples/`](examples/), grouped by topic (`01-basics` … `07-advanced`). `run_all_examples` plays a guided tour of the highlights.
 
 Full reference lives in the [Wiki](https://github.com/HanSur94/FastSense/wiki): Getting Started · API Reference · Architecture · MEX details · Performance.